At sea level. Furthermore according to the Kyoto Protocol Reference Manual parties. To safeguard national sovereignty, each international exchange of privately tradable emissions reduction units would require the permission of the concerned governments. Technically, companies could not use these credits, because they were meant for countries. This may seem paradoxical, given that these same companies will bear much of the burden, but they prefer a uniform situation worldwide rather than a patchwork of solutions so they can take this factor into account in their investments. Parties will need to decide on governance arrangements for the new mechanism. Carbon Markets USDA Forest Service.